Dear Kim, It is very likely that the markings on your knife block are reference points, not actual degree markings. If "0" has worked for you all along, then I would think that the vibrations are caused by something other than knife angle. If you are using disposable blades, there might be a variation in how high the edge of the blade sits above the top of the holder. If you are just starting out and have never really been happy with the quality of your cut sections then changing the angle could help. Since you are already at zero, make a slight change and see if that helps. Just remember, when you change the knife angle you change the orientation of block face to knife edge. Be careful not to damage your block and/or knife. If you have any questions, feel free to contact me off list. Regards, Dorothy Dorothy Traczyk MTA Histology LLC PO Box 602 Point Pleasant, NJ 08742 T: 732-899-2912 F: 732-899-5469 _doro...@mtahistology.com_ (mailto:doro...@mtahistology.com) _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet